Booster transformer switch

ABSTRACT

A switch, of pole-mounted type, adapted for connection, in an electrical power supply system, between a feed cable and a load cable; the switch, in one position, normally providing direct connection between the feed cable and the load cable, and, in another position, breaking such direct connection and establishing a by-pass connection -including a booster transformer-between the feed cable and load cable whereby to &#39;&#39;&#39;&#39;boost&#39;&#39;&#39;&#39; the current value in said load cable under a condition of undue voltage drop therein. The switch also provides a shunt operative to prevent the load cable from being taken completely out-of-circuit as the switch is actuated from said one position to such other position; said shunt-which includes a resistor-also serving to preload the booster transformer, with less than the full feed voltage, before the switch closes in such other position.

ited States Patent Pahl 1 June 27, 1972 [54] BOOSTER TRANSFORMER SWITCHPrimary Examiner-Hennan .l. Hohauser Attorney-Webster & Webster [72)Inventor: John G. Plhl, 1624 E. Al ine Ave.,

Stockton. Calif. 95205 p [571 ABSTRACT [22] Filed: March 2. A switch, ofpole-mounted type. adapted for connection, in an electrical power supplysystem, between a feed cable and a PP 127,567 load cable; the switch, inone position. normally providing direct connection between the feedcable and the load cable. and. in another position, breaking such directconnection and [52] [1.8. CI. JOB/48 R establishing a by-pass connection-including a booster trans- [Sl] Int. Cl. ..H0lh 31/00 former-betweenthe feed cable and load cable whereby to [58] Field of Search ....200/48R, 48 RP. 49, 50; boost" the current value in said load cable under acondition 307/112. I7, 85. 86, 87, 149 of undue voltage drop therein.The switch also provides a shunt operative to prevent the load cablefrom being taken Relerences Cited completely out-of-circuit as theswitch is actuated from said one position to such other position; saidshunt-which in- UNITED STATES PATENTS cludes a resistor-also serving topreload the booster trans- 3,274,364 9/1966 Sullivan et al ..200/4a uxformer. with less than the full feed voltagebefore the switch 3,553,4121/1971 Kerr ....2oo/4s R closes"! such othflpositioh 7 Claims, 6 DrawingFigures PATENTEflJum r912 SHEET 10F 2 Q3 IF INVENTOR.

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soos'rsa ramsroamsa swrrcl-r BACKGROUND OF THE INVENTION When thecurrent value in a load cable, of an electrical power supply system,substantially reduces as a result of the demand thereon, the voltagedrop is compensated for by means of a booster transformer theninterposed between the feed cable and such load cable. This must beaccomplished by a switch adapted for the purpose, and the presentinvention was conceived in the course of efforts to produce such aswitch of pole-mounted type and one having commercial advantage bothfrom the standpoint of ready manufacture and effective operation.

SUMMARY OF THE INVENTION The present invention provides, as a majorobject, a polemounted dual-position switch adapted for manual actuationbetween one position in which the switch provides a direct connectionbetween a feed cable and a load cable, and another position in whichsaid direct connection is broken and s by-pass connection-including abooster transformer-is established between the feed cable and load cablefor the purpose of boosting the voltage in said load cable when an unduevoltage drop occurs in the latter.

The present invention provides, as another object, a switch, as above,which includes a shunt automatically brought into play when the switchis actuated from said one position to such other position; the functionof the shunt, which includes a resistor, being to prevent the load cablefrom being taken completely out-of-circuit as the switch is so actuated,and to pre-load the booster transformer, with less than full feedvoltage, before the switch closes in such other position.

The present invention provides, as a further object, a boostertransformer switch which is designed for ease and economy ofmanufacture.

The present invention provides, as a still further object, a practical,reliable, and durable booster transformer switch, and one which isexceedingly effective for the purpose for which it is designed.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a side elevation of theswitch in its position providing direct connection between the feedcable and load cable.

FIG. 2 is a top plan of the switch as in FIG. I.

FIG. 3 is an end elevation of the same.

FIGS. 4, 5, and 6 are diagrammatic illustrations of certain positions ofthe switch.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now more particularlyto the drawings and to the characters of reference marked thereon, theswitch comprises, on a suitable mount l on a cross arm 2 of the pole P,a pair of spaced end-to-end insulators 3 and 4 disposed substantiallyhorizontally; the insulator 3 being rotatably secured at its inner endto the mount I in a known manner, and rotation of such insulator beingaccomplished by the usual lever 5 adapted to connect to a push-pull rodR. At its outer end, the insulator 3 is connected to the feed cable 6 ofthe circuit phase to which the switch is related. The insulator 4, whichis nonrotatably secured to the mount 1, is connected at the outer end tothe load cable 7.

The rotatable insulator 3 carries a generally L-shaped arm 8 having ablade 9 at its outer end; such blade normally engaging in a clip 10 onthe outer end of a generally L-shaped arm II carried by thenon-rotatable insulator 4. As shown, the feed cable 6 and load cable 7are electrically connected to the blade 9 and clip M, respectively.

The arms 8 and II, which are opposed, are shaped so thatupon part-circlerotation of insulator 3 and arm 8 by lever 5 and in a givendirection-blade 9 escapes clip I0 and swings upwardly and inwardlythrough an arc in the vertical longitudinal plane of the cross arm 2.

A third insulator 12 is secured to the mount 1 and projects upwardlyadjacent the insulators 3 and 4 and at a right angle to the axisthereof; the insulator 12 being fitted at its outer end with a short,rigid arm I3 which carries a clip 14 at its outer end. The clip 14 isdisposed in the same transverse vertical plane as the clip I0 and facesthe latter in spaced relation. The arrangement is such that-uponrotation of insulator 3 in the proper direction and resultant swingingof the arm 8-blade 9 escapes from clip 10 and engages in clip I4.

When the blade 9 is fully engaged in clip 10, the switchwhich is then inits normal position-provides a direct connection between the feed cable6 and the load cable 7. See, for example, FIGS. 2 and 4. However, uponthe occurrence of a load condition which causes an undue voltage drop inthe load cable 7, the switch is actuated to cause blade 9 to escape clip10 and fully engage in clip 14 as previously described. See FIG. 6. Whenblade 9 isso engaged in clip 14, a by-pass circuit orconnection-including a pole-mounted booster transformer 15 showndiagrammatically in FIGS. 2, 4, 5, and 6-is established between the feedcable 6 and load cable 7.

More particularly, such by-pass connection includes, together with blade9 and clip I4, leads I6 which couple the clip l4 to one side of thetransformer, and a lead 17 which extends from the other side of thetransformer to the load cable 7.

Thus, when the described by-pass circuit or connection is closed andoperative, the booster transformer l5 functions to return the voltage inload cable 7 to the requisite value. Thereafter, when the load conditionwhich caused the undue voltage drop is relieved, the switch is returnedto its normal position with blade 9 free of clip l4 and engaged in clip10.

In order to preclude the load cable from being taken whollyout-of-circuit when the switch is actuated from its direct-connectionposition (blade 9 engaged in clip ill), to its by-pass or "booster"position (blade 9 engaged in clip 14), and further to pre-load thetransformer IS with less than full feed voltage before the switch closesin said by-pass position, a shunt is provided as follows:

An oval-shaped, spring blade wiper I8 is disposed adjacent and parallelto the transverse vertical plane occupied by the clips 10 and I4; suchwiper l8 being positioned for electricalcontact engagement by the blade9 as the latter swings in an are between said clips. The configuration,size, and position of the wiper 18 is such that the blade 9, as it is soswung, engages with such wiper l8 before total disengagement from clip10 as shown in broken lines in FIG. 5, and initially engages with theclip I before total disengagement from said wiper as shown in brokenlines in FIG. 6.

The wiper I8 is suspended in position by a bracket I9 on the adjacentend of a dielectric rod 20 which, in turn, is held in a fixed positionby a bracket 21 secured on an arm 22 radiating from the outer end ofinsulator I2; the arm 22 being in electrical connection with the lead 16running to transformer IS.

A resistor 23 of predetermined capacity is attached to, and spansbetween, the brackets I9 and 21 whereby to establish a resistor circuitbetween the wiper I8 and the lead 16.

From the above description of the shunt, it will be recognized that asthe switch is actuated from its direct-connection position to itsby-pass position, there is no interruption of current flow from the feedcable 6 to the load cable 7; the blade 9, before it escapes the clip I0,engaging the wiper 18 so that when such escape takes place a circuit-atless than full feed volate-is established through the resistor 23 to thebooster transformer 15 (to pre-load the same), and thence to said loadcable 7. Then, after the blade 9 initially engages clip 14, said bladeescapes the wiper l8 and makes full engagement with clip I4 whereby theshunt is dropped out, the by-pass circuit is completed to thetransformer, and the latter is energized directly from the feed cable 6.

From the foregoing description, it will be readily seen that there hasbeen produced such a booster transformer switch as substantiallyfulfills the objects of the invention, as set forth herein.

I claim:

i. A pole-mounted switch adapted for use in connection with a feedcable, a load cable, and a booster transformer; comprising a mount, apair of insulators secured to and projecting from the mount, oneinsulator being rotatable and the other insulator non-rotatable, arms onsuch insulators extending to outer end terminations normally in adjacentrelation, a blade on the outer end of the arm corresponding to said oneinsulator. a clip on the outer end of the arm corresponding to saidother insulator, the blade normally engaging in the clip but beingdisengagable therefrom upon part-circle rotation of said one insulatorin a predetermined direction, the feed cable being connected to said oneinsulator and the blade, the load cable being onnected to said otherinsulator and the clip, a third insulator secured to and projecting fromthe mount in spaced relation to said pair of insulators, a supportingarm on and extending from the third insulator, a separate clip on suchsupporting arm and disposed thereby for engagement by said blade uponsuch part-circle rotation of said one insulator and resultant swingingof the blade away from said first-named clip, there being a by-passcircuit leading from said separate clip to the load cable, the boostertransformer being interposed in such by-pass circuit, one bracketsupported from said third insulator, a second bracket disposed in spacedrelation to said one bracket, a dielectric rod fixed with and spanningbetween such brackets, a wiper secured in connection with said secondbracket and positioned for contact by the blade during said swingingthereof, the wiper being formed and disposed so that the blade, uponsuch swinging thereof, makes contact with the wiper before disengagementfrom said firstnamed clip and thereafter makes contact with saidseparate clip before disengagement from said wiper, a resistor connectedto and spanning between said brackets, and means providing electricalconnection between said one bracket and the booster transformer.

2. A pole-mounted switch adapted for use in connection with a feedcable, a load cable, and a booster transformer; comprising a mount, apair of insulators secured to and projecting from the mount, oneinsulator being rotatable and the other insulator non-rotatable, arms onsuch insulators extending to outer end terminations normally in adjacentrelation, a blade on the outer end of the arm corresponding to said oneinsulator, a clip on the outer end of the arm corresponding to saidother insulator, the blade normally engaging in the clip but beingdisengagable therefrom upon part-circle rotation of said one insulatorin a predetermined direction, the feed cable being connected to said oneinsulator and the blade, the load cable being connected to said otherinsulator and the clip, a third insulator secured to and projecting fromthe mount in spaced relation to said pair of insulators, a supportingarm on and extending from the third insulator, a separate clip on suchsupporting arm and disposed thereby for engagement by said blade uponsuch part-circle rotation of said one insulator and resultant swingingof the blade away from said first-named clip, there being a by-passcircuit leading from said separate clip to the load cable, the boostertransformer being interposed in such by-pass circuit, a shunt comprisedof a wiper positioned for contact by the blade during said swingingthereof, and a shunt circuit extending from the wiper to the boostertransformer.

3. A switch, as in claim 2, in which the wiper is formed and disposed sothat the blade, upon such swinging thereof, makes contact with the wiperbefore disengagement from said firstnamed clip.

4. A switch, as in claim 3, in which the wiper is formed and disposed sothat the blade, upon such swinging thereof, makes contact with saidseparate clip before disengagement from said wiper.

5. A switch, as in claim 2 including a resistor interposed in such shuntcircuit.

6. A switch, as in claim 2 in which the wiper is formed and disposed sothat the blade, upon such swinging thereof, makes contact with the wiperbefore disengagement from said firstnamed clip and thereafter makescontact with said separate clip before disengagement from said wiper,

. A switch, as in claim 6, Including a resistor interposed in such shuntcircuit.

i i i Q III

1. A pole-mounted switch adapted for use in connection with a feedcable, a load cable, and a booster transformer; comprising a mount, apair of insulators secured to and projecting from the mount, oneinsulator being rotatable and the other insulator nonrotatable, arms onsuch insulators extending to outer end terminations normally in adjacentrelation, a blade on the outer end of the arm corresponding to said oneinsulator, a clip on the outer end of the arm corresponding to saidother insulator, the blade normally engaging in the clip but beingdisengagable therefrom upon part-circle rotation of said one insulatorin a predetermined direction, the feed cable being connected to said oneinsulator and the blade, the load cable being onnected to said otherinsulator and the clip, a third insulator secured to and projecting fromthe mount in spaced relation to said pair of insulators, a supportingarm on and extending from the third insulator, a separate clip on suchsupporting arm and disposed thereby for engagement by said blade uponsuch part-circle rotation of said one insulator and resultant swingingof the blade away from said first-named clip, there being a by-passcircuit leading from said separate clip to the load cable, the boostertransformer being interposed in such by-pass circuit, one bracketsupported from said third insulator, a second bracket disposed in spacedrelation to said one bracket, a dielectric rod fixed with and spanningbetween such brackets, a wiper secured in connection with said secondbracket and positioned for contact by the blade during said swingingthereof, the wiper being formed and disposed so that the blade, uponsuch swinging thereof, makes contact with the wiper before disengagementfrom said first-named clip and thereafter makes contact with saidseparate clip before disengagement from said wiper, a resistor connectedto and spanning between said brackets, and means providing electricalconnection between said one bracket and the booster transformer.
 2. Apole-mounted switch adapted for use in connection with a feed cable, aload cable, and a booster transformer; comprising a mount, a pair ofinsulators secured to and projecting from the mount, one insulator beingrotatable and the other insulator non-rotatable, arms on such insulatorsextending to outer end terminations normally in adjacent relation, ablade on the outer end of the arm corresponding to said one insulator, aclip on the outer end of the arm corresponding to said other insulator,the blade normally engaging in the clip but being disengagable therefromupon part-circle rotation of said one insulator in a predetermineddirection, the feed cable being connected to said oNe insulator and theblade, the load cable being connected to said other insulator and theclip, a third insulator secured to and projecting from the mount inspaced relation to said pair of insulators, a supporting arm on andextending from the third insulator, a separate clip on such supportingarm and disposed thereby for engagement by said blade upon suchpart-circle rotation of said one insulator and resultant swinging of theblade away from said first-named clip, there being a by-pass circuitleading from said separate clip to the load cable, the boostertransformer being interposed in such by-pass circuit, a shunt comprisedof a wiper positioned for contact by the blade during said swingingthereof, and a shunt circuit extending from the wiper to the boostertransformer.
 3. A switch, as in claim 2, in which the wiper is formedand disposed so that the blade, upon such swinging thereof, makescontact with the wiper before disengagement from said first-named clip.4. A switch, as in claim 3, in which the wiper is formed and disposed sothat the blade, upon such swinging thereof, makes contact with saidseparate clip before disengagement from said wiper.
 5. A switch, as inclaim 2 including a resistor interposed in such shunt circuit.
 6. Aswitch, as in claim 2 in which the wiper is formed and disposed so thatthe blade, upon such swinging thereof, makes contact with the wiperbefore disengagement from said first-named clip and thereafter makescontact with said separate clip before disengagement from said wiper. 7.A switch, as in claim 6, including a resistor interposed in such shuntcircuit.